1. Field of the Invention
The present invention relates, in general, to an aluminum alloy for a vehicle cylinder liner and a method of manufacturing a cylinder liner using the same.
Generally, a cylinder liner is fitted into a bore of an engine block, and serves to suitably prevent the bore from becoming abraded during the reciprocation of a piston. Currently, a cylinder liner, which is used to reinforce the bore of an aluminum cylinder block and adapted to suit the trend of decreasing the weight of engines for transport machines such as automobiles and the like, is mainly made of cast iron.
Recently, a cylinder liner made of aluminum extrusion has been used in an effort to improve the cooling performance of an engine and decrease the weight of an engine in accordance with the development of high-powered engines. Accordingly, the cylinder liner needs wear resistance. Therefore, in order to suitably improve the wear resistance of the cylinder liner, the amount of silicon included in an aluminum alloy is increased, and the size of silicon is miniaturized.
FIG. 1 is a schematic view showing an exemplary conventional method of manufacturing an aluminum cylinder liner using a spray forming method.
Conventionally, a spray forming method is used in order to suitably increase the amount of silicon included in a cylinder liner and miniaturize the size of silicon. In the spray forming method, a molten metal 1 (for example, molten aluminum) is rapidly cooled using high-speed high-pressure inert gases and then sprayed through a sprayer 10 to be formed into droplets 2. The droplets 2 drop in the air are in a state of incomplete solidification, and then are completely solidified after they reach a substrate 20, thus forming a round bar 21.
Subsequently, the round bar 21 formed using the spray forming method is manufactured into a cylinder liner through indirect extrusion (hot extrusion) and then swaging and then cutting and working and then surface treatment.
However, as described above, in the conventional method of manufacturing an aluminum cylinder liner using a spray forming method the size of silicon can be miniaturized; however, at the same time the process of forming a round bar is complicated, and the formed round bar must be further extruded, thus increasing the production cost thereof.
Further, in the conventional method material loss occurs when holes are formed in the inner surface of a round bar in order to suitably conduct seamless extrusion at the time of the extrusion of the round bar.
Further, the conventional cylinder liner manufactured using the spray forming method is also problematic in that particles are too small in size, so that it is not easy to perform a machining process, and so a chemical etching process is used in order to allow hard particles to protrude, thereby causing environmental pollution.